Applicant's invention is directed toward a method and apparatus for treating sludge and other liquid waste streams, which contain a mixture of solids and liquids. Certain waste streams comprise a mixture of solid materials and water and in many instances, contain toxic materials, hazardous materials or heavy metals. Applicant's invention is directed toward the removal of water or other fluids in the waste stream such that the waste stream after treatment is substantially solid matter which can be either treated further or disposed.
Applicant's invention also provides substantial benefits with respect to hazardous or toxic substances contained in the waste stream. With respect to many toxic and hazardous materials, Applicant's device will neutralize the materials and at the same time sterilize pathogens and microorganisms contained in the sludge such that the resultant end product is a granulated solid which, in most cases, can be disposed of in sanitary landfills without any detriment to the environment. Applicant can accomplish this neutralization through the following procedure which represents substantial improvement in the amount of dewatering which can be accomplished with such a sludge stream thereby leaving the final product in a substantially solid, granulated form.
Applicant is the holder of U.S. Pat. No. 4,655,932 for a method and apparatus for the disintegration and destruction of hazardous and toxic sludge materials which utilize the process of blending the waste stream or sludge materials with an electrolyte to improve conductivity, partially dewatering the sludge stream in order to achieve a filter cake, pressing the filter cake to a desired thickness based on the conductivity of the filter cake and then subjecting the filter cake to electrical heat energy to drive off the remaining water resulting in a pulverized granular solid.
The present invention utilizes an electrolyte in combination with a mixed stream of solids and liquids, however, Applicant's final dewatering step utilizes a combination of electrical energy and pressure in order to substantially dewater water the material. Applicant's present invention has application to sludge streams or waste streams, but also to nonhazardous material in which there is a desire to remove the water content.